# fēnix 5 Freedive Depth Port — Implementation Outline

This document outlines how to port the existing fēnix 3 breath-hold app into a **depth-capable freediving app** for the **Garmin fēnix 5 / 5S / 5X / 5 Plus / 5S Plus / 5X Plus** family.

> **Why fēnix 5?** It is the best fēnix choice for a personal freedive depth logger: it exposes `Activity.Info.rawAmbientPressure` (API Level 2.4.0+), supports the user’s ANT+ HRM‑Tri chest strap, has physical buttons that work underwater, and forum/developer reports indicate it does **not** artificially cap underwater pressure readings. Newer fēnix 6 / 7 / 8 / Tactix models reportedly cap pressure around 3 m underwater, making them unsuitable for freediving depth despite also having the API.

---

## 1. Recommended Target Devices & API

| Device | CIQ API level | `rawAmbientPressure` | ANT+ HR | Water rating | Notes |
|--------|---------------|----------------------|---------|--------------|-------|
| fēnix 5 / 5S / 5X | ~3.1.x | ✅ | ✅ | 10 ATM | Base 5-series; use `ActivityRecording.SPORT_*` enums for safety |
| fēnix 5 Plus / 5S Plus / 5X Plus | ~3.2.x–3.3.x | ✅ | ✅ | 10 ATM | Plus models moved some enums to `Toybox.Activity` |
| fēnix 3 / 3 HR | 1.4.0 | ❌ | ✅ | 10 ATM | Keep as separate breath-hold build (no depth) |
| fēnix 6 / 7 / 8 / Tactix | 3.3+ / 4.x / 5.x | ✅ (capped ~3 m) | ✅ | 10 ATM | **Not recommended** for depth |

**Manifest choice for fēnix 5-only build:**

```xml
<iq:application entry="DiveApp" id="…" minApiLevel="2.4.0" type="watch-app">
    <iq:products>
        <iq:product id="fenix5"/>
        <iq:product id="fenix5s"/>
        <iq:product id="fenix5x"/>
        <iq:product id="fenix5plus"/>
        <iq:product id="fenix5splus"/>
        <iq:product id="fenix5xplus"/>
    </iq:products>
    <iq:permissions>
        <iq:permission id="Sensor"/>
        <iq:permission id="ActivityRecording"/>
        <iq:permission id="FitContributor"/>
    </iq:permissions>
</iq:application>
```

> **Note:** For a single app that also runs on fēnix 3, you must guard `rawAmbientPressure` with `has` checks and be careful with compiler optimization. For a personal sideload, the cleanest approach is a **separate fēnix 5 build** (`manifest_fenix5.xml` + a second `.jungle` file), which is what this outline assumes.

---

## 2. What the fēnix 5 App Would Do

Keep the working breath-hold / surface features from the fēnix 3 app and add **true depth logging**:

- **Surface calibration** before the first dive.
- **Depth tracking** during the dive (current depth, max depth, dive time).
- **Surface interval** timer between dives.
- **Breath-hold prep / hold / recovery** timer (optional, useful for static sessions at the surface).
- **Contraction counter** and **manual pool-length counter** (optional, since horizontal distance still has no sensor).
- **Heart-rate logging** from HRM‑Tri or wrist sensor.
- **FIT recording** with a depth graph plus session summary fields.

> **What “underwater distance” means on fēnix 5:** The watch measures **vertical depth**, not horizontal/3-D travel distance. GPS does not work underwater, and accelerometer dead-reckoning drifts too fast. If you also want horizontal distance in a pool, keep the manual `lengths × pool length` feature.

---

## 3. New / Changed Files

| File | Purpose |
|------|---------|
| `manifest_fenix5.xml` | fēnix 5-only manifest (products + `minApiLevel="2.4.0"`) |
| `monkey_fenix5.jungle` | Points to `manifest_fenix5.xml` and optionally a `source/fenix5/` overlay |
| `source/DepthModel.mc` | Constants, surface-pressure calibration, depth calculation, water-type density |
| `source/DiveView.mc` | Main view: shows depth, dive time, max depth, HR, lengths, contractions |
| `source/DiveDelegate.mc` | Button handling; adds depth-related actions if desired |
| `source/Settings.mc` | Add `isSaltWater` to existing pool-length settings |
| `source/PoolLengthView.mc` | Add a fresh/salt-water toggle screen or toggle in the same picker |
| `source/FitFields.mc` *(optional)* | Helper that creates all `FitContributor` fields |
| `README.md` | Add fēnix 5 build/sideload instructions |

---

## 4. Depth Calculation

`Activity.Info.rawAmbientPressure` is the **absolute ambient pressure in Pascals** (uncalibrated). Depth is computed from the pressure difference versus a calibrated surface pressure.

```monkey-c
using Toybox.Activity;
using Toybox.System;

const G = 9.80665;
const RHO_FRESH = 997.0;  // kg/m³
const RHO_SALT  = 1023.0; // kg/m³

class DepthModel {
    static var surfacePressure = null;
    static var isSaltWater = false;

    // Call while the watch is floating calmly at the surface.
    static function calibrate() {
        var info = Activity.getActivityInfo();
        if (info != null && info has :rawAmbientPressure && info.rawAmbientPressure != null) {
            surfacePressure = info.rawAmbientPressure;
        }
    }

    static function depthM() {
        if (surfacePressure == null) { return null; }
        var info = Activity.getActivityInfo();
        if (info == null || !(info has :rawAmbientPressure) || info.rawAmbientPressure == null) {
            return null;
        }
        var rho = isSaltWater ? RHO_SALT : RHO_FRESH;
        var deltaP = info.rawAmbientPressure - surfacePressure;
        var d = deltaP / (rho * G);
        return (d < 0.0) ? 0.0 : d; // clamp negative splash noise to 0
    }
}
```

### Calibration strategy

1. **Auto-calibrate on first START** while the user is on the surface.
2. **Manual re-calibrate** via long-press START or a menu item if the surface pressure drifts.
3. For best accuracy, take a short average (3–5 samples) during calibration rather than a single reading.

---

## 5. FIT Field Plan

### Per-`RECORD` (depth graph)

| Field name | ID | Type | Units | Notes |
|------------|----|------|-------|-------|
| `depth_m` | 0 | `FLOAT` | m | Written every second during the dive |
| `hr_bpm` *(optional)* | 1 | `UINT8` | bpm | Redundant with native HR but convenient |

### Per-`SESSION` (summary)

| Field name | ID | Type | Units | Notes |
|------------|----|------|-------|-------|
| `max_depth_m` | 2 | `UINT16` | m | Deepest point of the session |
| `best_hold_time_s` | 3 | `UINT16` | s | Same as existing `hold_time_s` |
| `last_hr_bpm` | 4 | `UINT8` | bpm | Last sampled heart rate |
| `surface_interval_s` | 5 | `UINT16` | s | Time since last dive ended |
| `horizontal_distance_m` | 6 | `UINT16` | m | From manual pool-length counting |
| `length_count` | 7 | `UINT8` | laps | Number of manually counted lengths |

### Why not write the standard Garmin `distance` field?

Because the watch cannot measure true underwater travel distance. Writing Garmin’s standard `distance` field would produce a misleading graph. Use custom developer fields only.

---

## 6. Suggested UI Layout (fēnix 5 240 × 240 MIP)

```
+------------------+
|  SURFACE  SALT   |  <- state + water type
|                  |
|      0.0 m       |  <- current depth (big)
|                  |
|  MAX 12.3m  1:23 |  <- max depth / dive or hold time
|  HR 58  L3 D75m  |  <- HR + manual length/distance
|  UP=LAP DOWN=CONT|  <- hint
+------------------+
```

States:

- `IDLE` — show last session max depth, selected pool length, water type. START begins prep/calibration.
- `SURFACE` — waiting at surface; show current depth (0.0 m), surface interval. START marks “begin dive / begin hold.”
- `DIVE` / `HOLD` — show current depth prominently, dive time below it, max depth.
- `RECOVERY` / `SURFACE_INTERVAL` — show surface interval timer, last max depth, HR.
- `DONE` — summary screen.

Button mapping (kept close to fēnix 3 version):

| Button | Action |
|--------|--------|
| **START** | Begin session / start dive / end dive / finish recovery |
| **UP** | Count a pool length (manual horizontal distance) |
| **DOWN** | Count a contraction |
| **BACK short** | Exit (idle) / discard (active) |
| **BACK long** | Open settings (pool length + fresh/salt) |

Optional extra: **long-press START** from surface to force a surface-pressure re-calibration.

---

## 7. Build & Sideload

1. Install the Connect IQ SDK and the fēnix 5 / 5S / 5X / 5 Plus device files.
2. Build using the fēnix 5 manifest:
   ```bash
   monkeyc -d fenix5 -f monkey_fenix5.jungle -o bin/FreediveDepth_fenix5.prg -y developer_key.der
   ```
3. Sideload the `.PRG` to `GARMIN/APPS/` over USB mass-storage mode.
4. Test first in a pool, comparing depth against a known reference (pool floor depth, dive line, or a dedicated dive computer).

---

## 8. Risks & Open Questions

| Risk | Impact | Mitigation |
|------|--------|------------|
| fēnix 5 is **not dive-rated** by Garmin | Warranty / water-damage risk outside stated use | Use at own risk; rinse after salt water; inspect seals |
| Future firmware may cap pressure like fēnix 6/7/8 | Depth readings stop below ~3 m | Pin CIQ/firmware version if possible; test after any watch update |
| Surface pressure drift (waves, weather, temperature) | Depth offset | Re-calibrate before each dive; average several samples |
| Raw pressure sensor noise / temperature hysteresis | ±0.1–0.3 m jitter | Light filtering; clamp negative values to 0 |
| Memory / recording limits on long sessions | App crash or lost data | Keep depth as `FLOAT` record; test 5+ min sessions |
| HRM‑Tri optical/chest strap underwater | HR dropouts at depth | Accept as log-only; not a safety instrument |

---

## 9. Decisions Needed Before Coding

1. **Unified app or separate fēnix 5 build?**
   *Recommended:* separate `manifest_fenix5.xml` / `monkey_fenix5.jungle` to avoid `has`-check optimizer surprises.
2. **Keep breath-hold prep/recovery and pool-length features?**
   *Recommended:* keep them — they are useful for static training and pool swims.
3. **Auto vs manual surface-pressure calibration?**
   *Recommended:* auto-calibrate on first START, with a manual re-calibrate option.
4. **Add depth alarms?**
   (e.g., vibrate at target depth) — nice-to-have, but adds complexity and battery use.
5. **Target model order?**
   Build for `fenix5` first (most common), then `fenix5s` / `fenix5x` / `fenix5plus` variants.

---

## 10. Summary of the “Best fēnix” Choice

For a personal, sideloaded freediving app, the **fēnix 5 / 5S / 5X / 5 Plus / 5S Plus / 5X Plus** family is the sweet spot:

- Has the raw ambient pressure API and **reportedly uncapped** underwater readings.
- Works with the user’s existing **HRM‑Tri** ANT+ chest strap.
- Physical buttons work underwater.
- Cheaper and easier to source used than a Garmin Descent.

The main caveats are Garmin’s “not dive-rated” disclaimer and the fact that horizontal/3-D underwater distance is still impossible on any wrist device.


Now I need to create a comprehensive plan for the user's new requirements. They want:

1. Main menu at start to choose between:
   - Depth type
   - Distance
   - Static apnoe test
   - Breathing trainer (on land)

2. For each type, specific features:
   - Depth type:
     - Constant weight (submenu: bifin, monofin, nofin)
     - Free Immersion (FIM) - this is what "immersions" is called
     - Strokes count
     - Speed? (question mark - need to address feasibility)
     - Depth
     - HR
     - Breathhold time
     - Menu for breathing break / breath up function (normally 2min or with button press)

   - Distance:
     - Submenu: bifin, monofin, nofin
     - Strokes count
     - Speed?
     - Distance
     - HR
     - Breathhold time
     - Breathing break / breath up function

   - Static apnoe test:
     - Breath up timer
     - Breathhold time
     - HR
     - Depth (probably just 0 since it's static, but maybe they want pressure?)

   - Breathing trainer (on land):
     - Predefined breathhold time manual entry
     - Breaks get shorter: 3min, 2.5min, 2min, 1.5min, 1min

This is a major architectural change. I need to:

1. Update PORT_FENIX5.md with the new menu structure, OR create a new plan document
2. Possibly ask some clarifying questions but I can also present the plan with assumptions
3. Note feasibility of "speed" (not feasible without GPS or accelerometer integration - which drifts too fast underwater)

I think I should create a new structured plan document: `APP_MENU_PLAN.md` or update `PORT_FENIX5.md`. Given the user is talking about the fēnix 5 port specifically, I should probably update PORT_FENIX5.md to reflect this new menu-based design. Or create a new `DESIGN_V2.md`.

Let me also consider: the user mentioned "different screen or even function" for distance. So distance should be a completely separate mode from depth, not just an extra field.

I should:
1. Confirm the terminology: "immersions" in freediving = "Free Immersion" (FIM)
2. Create a structured design document
3. Note that "speed" and "strokes count" are problematic on fēnix because:
   - Speed: no GPS underwater, accelerometer dead reckoning is unreliable
   - Strokes count: third-party apps cannot access native accelerometer stroke detection reliably, but could try to detect arm strokes via accelerometer data. Actually, CIQ API does expose accelerometer data on fēnix 5 (Sensor.SENSOR_ACCELEROMETER). But processing it for stroke counting is complex. We could implement a manual stroke counter (button press per stroke) which is more reliable.
4. Breathing break / breath up: 2 min default, can be skipped/started with button press
5. Breathing trainer: cycles of breath hold with decreasing break times

Given the complexity, I think I should create a new design document and present it, then ask if they want me to start implementing. I should also ask a few clarifying questions about:
- Strokes count: manual button press or automatic accelerometer-based?
- Speed: do they want this despite it being unreliable, or just skip it?
- Breathing trainer: number of cycles? Can they adjust starting hold time?
- Do they want a unified fēnix 3/5 app or separate builds?

But the instructions say use ask_user_question when underspecified. The request has some ambiguities (speed?, strokes count method). I think I should create the plan first with my assumptions clearly stated, then ask targeted questions. Or I could ask the questions now.

Actually, looking at the conversation flow, the user has been giving me increasingly detailed requirements. I should respond with a comprehensive plan and note where I need decisions. Let me create a design document and present it.

I'll update PORT_FENIX5.md to version 2 with the menu structure, or create APP_DESIGN.md. Given the user wants to keep fēnix 3 too, I should make this applicable to both (with depth only on fēnix 5). Let me create `APP_DESIGN_V2.md`.

Actually, since this is a substantial redesign, I'll create a new document and update the README and IMPLEMENTATION_PLAN to reference it.

Let me structure the document:
1. Discipline terminology confirmed
2. Top-level menu structure
3. Per-mode details
4. Screen layouts
5. Button mapping per mode
6. FIT fields
7. Files to add/change
8. Open decisions needed from user
9. Implementation phases

Let me write this now.

write

# Freedive App v2 Design — Main Menu + Multiple Disciplines

This document re-designs the app around a **main menu at launch** that lets you pick the discipline you are training. It is written primarily for the fēnix 5 depth build, but the non-depth modes also work on fēnix 3 (where depth simply stays 0 and `depth_m` is not written).

> **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.

---

## 1. Main Menu at Launch

When the app starts, the first screen is a 4-item menu:

```
+------------------+
|  FREEDIVE MODE   |
|                  |
| > Depth          |
|   Distance       |
|   Static Apnoe   |
|   Breathing Tr.  |
+------------------+
```

Navigation: **UP/DOWN** move the highlight, **START** selects the mode, **BACK** exits the app.

After selecting a mode you get a second menu for **fin type** (where applicable) or go straight into the session setup.

---

## 2. Mode: Depth

Sub-menu for fin type (only affects the FIT label; the watch still only measures vertical depth):

```
+------------------+
|  DEPTH FIN TYPE  |
|                  |
| > Constant Weight|
|   Free Immersion |
+------------------+
```

After choosing the discipline, choose the fin style (only relevant for Constant Weight):

```
+------------------+
|  CWT FIN STYLE   |
|                  |
| > Bi-fins        |
|   Monofin        |
|   No-fins (CNF)  |
+------------------+
```

Then choose the breath-up/breathing break length:

```
+------------------+
|   BREATH UP      |
|                  |
| > 2:00 min       |
|   Skip (manual)  |
|   Custom...      |
+------------------+
```

### Depth session screens

| Screen | Top | Big value | Bottom line |
|--------|-----|-----------|-------------|
| Breath up | timer counting down | `2:00` | depth 0.0 m / HR / press START to skip |
| Surface ready | `SURFACE` | `0.0 m` | max depth, HR, surface interval |
| Dive | fin style + water type | current `depth_m` | dive time, max depth, HR |
| Recovery/surface interval | `RECOVERY` | surface timer | last max depth, HR |
| Done | summary | `MAX 24.3 m` | dive time, HR, fin style |

### Fields recorded for Depth

Custom FIT developer fields per **session**:

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `discipline` | STRING | text | e.g. `CWTB`, `CWT-M`, `CNF`, `FIM` |
| `max_depth_m` | UINT16 | m | deepest point of this dive |
| `dive_time_s` | UINT16 | s | time from start of dive to surfacing |
| `surface_interval_s` | UINT16 | s | time since previous dive ended |
| `breath_up_time_s` | UINT16 | s | breath-up duration used |
| `last_hr_bpm` | UINT8 | bpm | last sampled HR before save |

Custom FIT developer fields per **record** (1 Hz graph):

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `depth_m` | FLOAT | m | current depth |
| `hr_bpm` | UINT8 | bpm | current heart rate |

> **About "strokes count" and "speed":** The watch has no reliable way to measure these underwater. GPS does not work underwater, and accelerometer dead-reckoning for speed/stroke detection drifts too fast to be useful in a third-party app. The practical options are:
> - **Manual stroke counter:** press UP for every arm stroke. We can add this if you want it.
> - **Skip speed/strokes** and rely on depth + time instead.

---

## 3. Mode: Distance

This is a **separate function** with its own flow. It measures horizontal pool distance only (manual `lengths × pool length`), with optional breath-hold timer.

Sub-menu:

```
+------------------+
| DISTANCE FIN TYPE|
|                  |
| > Bi-fins        |
|   Monofin        |
|   No-fins (DNF)  |
+------------------+
```

Then pool-length picker (25 m / 50 m / custom) and breath-up length (2:00 / manual / custom).

### Distance session screens

| Screen | Top | Big value | Bottom line |
|--------|-----|-----------|-------------|
| Breath up | timer counting down | `2:00` | pool length, HR, START=skip |
| Hold / swim | `DYN` + fin style | `0:00` breath-hold time | distance, lengths, HR, UP=LAP, DOWN=STROKE |
| Recovery | `RECOVERY` | recovery timer | total distance, lengths, HR |
| Done | summary | `D 75 m` | hold time, HR, lengths |

### Fields recorded for Distance

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `discipline` | STRING | text | e.g. `DYN-B`, `DYN-M`, `DNF` |
| `horizontal_distance_m` | UINT16 | m | `lengthCount × poolLengthM` |
| `length_count` | UINT8 | laps | manually counted lengths |
| `stroke_count` | UINT8 | strokes | manual stroke counter if enabled |
| `breathhold_time_s` | UINT16 | s | best breath-hold of the swim |
| `breath_up_time_s` | UINT16 | s | breath-up duration used |
| `last_hr_bpm` | UINT8 | bpm | last sampled HR |

Distance mode intentionally does **not** write a standard Garmin `distance` field.

---

## 4. Mode: Static Apnoe (STA)

No fin selection needed. The session is a surface breath-hold timer with HR.

Sub-menu or direct session:

- Breath up: 2:00 default, or manual, or custom.
- Hold: counts up until START is pressed.
- Recovery: 2:00 default, or manual, or custom.

### Static session screens

| Screen | Top | Big value | Bottom line |
|--------|-----|-----------|-------------|
| Breath up | `BREATH UP` | countdown | HR, START=skip |
| Hold | `HOLD` | elapsed time | HR, START=end hold |
| Recovery | `RECOVERY` | countdown | HR, START=finish |
| Done | `SAVED` | best hold time | HR |

### Fields recorded for Static Apnoe

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `discipline` | STRING | text | `STA` |
| `breathhold_time_s` | UINT16 | s | best breath-hold |
| `breath_up_time_s` | UINT16 | s | breath-up duration used |
| `recovery_time_s` | UINT16 | s | recovery duration used |
| `last_hr_bpm` | UINT8 | bpm | last sampled HR |

`depth_m` is not recorded in Static mode because the watch stays on the surface.

---

## 5. Mode: Breathing Trainer (on land)

A structured CO₂ / O₂ table trainer. The user enters a target breath-hold time; the app then cycles through breath-holds with **decreasing rest times**.

Default rest series (editable in settings):

```
3:00 → 2:30 → 2:00 → 1:30 → 1:00
```

Each cycle:

1. **Breathe (rest)** — countdown from current rest time.
2. **Breath hold** — hold for the user-entered target time (counts down).
3. If more cycles remain, reduce rest by one step and repeat.

### Breathing trainer screens

| Screen | Top | Big value | Bottom line |
|--------|-----|-----------|-------------|
| Setup | `HOLD TARGET` | `2:00` | UP/DOWN adjust, START=next |
| Rest setup | `REST START` | `3:00` | UP/DOWN adjust, START=begin |
| Breathe | `BREATHE` | rest countdown | cycle N/5, HR |
| Hold | `HOLD` | hold countdown | cycle N/5, HR |
| Done | `FINISHED` | total hold time | cycles completed, HR |

### Fields recorded for Breathing Trainer

Because this is on land, no `ActivityRecording` session is strictly needed, but we can record a lightweight generic session for tracking:

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `discipline` | STRING | text | `BREATHE` |
| `hold_target_s` | UINT16 | s | target breath-hold time |
| `cycles_completed` | UINT8 | count | how many cycles finished |
| `total_hold_time_s` | UINT16 | s | sum of all completed holds |
| `last_hr_bpm` | UINT8 | bpm | last sampled HR |

Optionally, each completed hold could be recorded as a **lap** with lap fields:

| Field | Type | Units | Meaning |
|-------|------|-------|---------|
| `lap_hold_s` | UINT16 | s | hold time for this lap |
| `lap_rest_s` | UINT16 | s | rest time before this hold |

---

## 6. Settings / Configuration

Long-press **BACK** from any menu or idle screen opens a settings menu:

```
+------------------+
|    SETTINGS      |
|                  |
| > Pool length    |
|   Water type     |
|   Default breath |
|   Rest series    |
|   HR sensor      |
+------------------+
```

- **Pool length** — 25 m / 50 m / custom (used by Distance mode).
- **Water type** — Fresh / Salt (used by Depth mode for density).
- **Default breath-up** — 2:00 / 1:30 / custom (default for Depth, Distance, Static).
- **Rest series** — the 5-step rest series for Breathing Trainer.
- **HR sensor** — Auto / ANT+ only / wrist only (best-effort; actual pairing happens outside the app).

---

## 7. Button Mapping by Context

### Main menu / sub-menu

| Button | Action |
|--------|--------|
| UP | Previous item |
| DOWN | Next item |
| START | Select / confirm |
| BACK short | Back one level / exit app if at top |
| BACK long | Open Settings |

### Active session (Depth / Distance / Static / Breathing)

| Button | Action |
|--------|--------|
| START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
| UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
| DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
| BACK short | Discard session and return to main menu |
| BACK long | Open in-session settings (rarely used) |

> **Open decision:** in Distance mode, should DOWN count **strokes** or **contractions**? They are different metrics. We could add a setting to choose which one DOWN counts.

---

## 8. Code Structure Changes

A single-file `BreathHoldView` is no longer enough. Proposed new files:

| File | Responsibility |
|------|--------------|
| `source/MainMenuApp.mc` | App entry point; loads settings; returns the main menu view |
| `source/MainMenuView.mc` + `MainMenuDelegate.mc` | Top-level 4-item menu |
| `source/SubMenuView.mc` + `SubMenuDelegate.mc` | Reusable 2–4 item sub-menu (fin type, breath-up length, etc.) |
| `source/Settings.mc` | Expanded persistence: pool length, water type, defaults, rest series |
| `source/DepthModel.mc` | Surface calibration, depth calculation, water density |
| `source/SessionState.mc` *(optional)* | Shared state machine constants and timer helpers |
| `source/DepthView.mc` + `DepthDelegate.mc` | Depth session UI and controls |
| `source/DistanceView.mc` + `DistanceDelegate.mc` | Distance session UI and controls |
| `source/StaticView.mc` + `StaticDelegate.mc` | Static apnoe session UI and controls |
| `source/BreathingView.mc` + `BreathingDelegate.mc` | Breathing trainer UI and controls |
| `source/FitRecorder.mc` *(optional)* | Central helper for creating/writing FIT fields per mode |
| `source/Common.mc` | Shared helpers (`formatTime`, HR sample, etc.) |

This is a significant refactor, but each mode becomes self-contained and easier to test.

---

## 9. FIT Field ID Allocation

Use a single ID space so one `.iq`/`.prg` does not collide. Recommended allocation:

| ID | Field | Message type |
|----|-------|--------------|
| 0 | `discipline` | SESSION |
| 1 | `depth_m` | RECORD |
| 2 | `hr_bpm` | RECORD |
| 3 | `max_depth_m` | SESSION |
| 4 | `dive_time_s` | SESSION |
| 5 | `surface_interval_s` | SESSION |
| 6 | `horizontal_distance_m` | SESSION |
| 7 | `length_count` | SESSION |
| 8 | `stroke_count` | SESSION |
| 9 | `breathhold_time_s` | SESSION |
| 10 | `breath_up_time_s` | SESSION |
| 11 | `recovery_time_s` | SESSION |
| 12 | `last_hr_bpm` | SESSION |
| 13 | `cycles_completed` | SESSION |
| 14 | `total_hold_time_s` | SESSION |
| 15 | `hold_target_s` | SESSION |
| 20 | `lap_hold_s` | LAP (Breathing trainer) |
| 21 | `lap_rest_s` | LAP (Breathing trainer) |

---

## 10. Implementation Phases

Because this is a large change, I suggest building it in phases:

1. **Phase 1 — Menu shell** (works on fēnix 3 too)
   - Replace the single `BreathHoldView` with `MainMenuView`.
   - Add sub-menu navigation.
   - Keep the existing Static/Recovery flow as one of the menu items.

2. **Phase 2 — Static Apnoe + Breathing Trainer** (works on fēnix 3 too)
   - Extract Static mode into its own view/delegate.
   - Add Breathing Trainer with configurable rest series and target hold.

3. **Phase 3 — Distance mode** (works on fēnix 3 too)
   - Move the manual pool-length logic out of the old breath-hold view into `DistanceView`.
   - Add fin-type selection and manual stroke counter.

4. **Phase 4 — Depth mode** (fēnix 5 only)
   - Create fēnix 5 build.
   - Add `DepthModel`, depth UI, depth FIT fields.

5. **Phase 5 — Polish**
   - Settings menu.
   - Common FIT helper.
   - README update.

---

## 11. Open Decisions Needed from You

Before I start coding, please confirm or correct these assumptions:

1. **Fin type selection** — keep the 3 options (bi-fins, monofin, no-fins) for both Depth and Distance?
2. **Free Immersion (FIM)** — should it appear under Depth alongside Constant Weight, or as its own top-level item?
3. **Strokes vs contractions** — in Distance mode, should DOWN count **strokes** (arm pulls) or **contractions**? We can make it configurable.
4. **Speed** — skip it entirely because it is not measurable underwater, or keep a manual stroke counter and derive an approximate average speed from `distance / breathhold_time` in the FIT summary?
5. **Breathing trainer defaults** — is the rest series `3:00 → 2:30 → 2:00 → 1:30 → 1:00` OK? How many cycles? Should target hold time be editable per session or only in settings?
6. **Build strategy** — should I implement the menu + non-depth modes first so they work on your existing fēnix 3, then create the fēnix 5 depth build?
7. **Depth on Static mode** — do you want the watch to also log depth/pressure while you do static breath-holds at the surface? (Normally it stays at 0 m.)

Once you confirm, I will start with **Phase 1** and update the code.


Successfully wrote 13600 bytes to /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md


Now I need to update the README and IMPLEMENTATION_PLAN to reference this new design document. Then present the plan to the user and ask for confirmation on the open decisions.

Let me update the README and IMPLEMENTATION_PLAN briefly, then provide a summary with the questions.


# Garmin fēnix 3 Freedive Breath App

A personal, sideloaded Connect IQ app for the **Garmin fēnix 3** and **fēnix 3 HR** that records static breath-hold sessions and heart rate to a FIT file.

> **Important:** This app does **not** measure depth. The fēnix 3 *hardware* measures ambient pressure and the native *Ambient Press.* data field displays it, but the Connect IQ API on fēnix 3 (API Level 1.4.0) only exposes `Sensor.Info.pressure`. That value is **sea-level calibrated** and auto-corrected for weather/altitude, so a third-party app cannot read the raw ambient pressure needed for depth.
>
> **For depth logging on a fēnix watch**, use a **fēnix 5 / 5S / 5X / 5 Plus / 5S Plus / 5X Plus**. These support `Activity.Info.rawAmbientPressure` (API Level 2.4.0+) and forum reports indicate they do not artificially cap underwater pressure. Avoid the **fēnix 6 / 7 / 8 / Tactix** for depth-based freediving: reports say Garmin caps pressure readings underwater around 3 m, even though the raw-pressure API is present.
>
> A Garmin **Descent** is the purpose-built alternative if you want a Garmin freediving computer.

---

## What it does

- **Static breath-hold timer** with three phases:
  1. **Prep breathe** (default 2 minutes, configurable in code)
  2. **Breath-hold** (counts up until you press START)
  3. **Recovery** (default 2 minutes, configurable in code)
- **Manual pool-length counter** during the hold phase (press **UP** each time you complete a pool length). Distance is `lengths × pool length`.
- **Contraction counter** during the hold phase (press **DOWN**).
- **Pool-length setting** — 25 m, 50 m, or custom (long-press **BACK** from the idle screen).
- **Heart-rate display** from the HRM‑Tri / HRM‑Swim ANT+ chest strap or fēnix 3 HR wrist sensor.
- **FIT recording** of the session with custom fields:
  - `hold_time_s` — best breath-hold time of the session
  - `last_hr_bpm` — last sampled heart rate
  - `horizontal_distance_m` — total horizontal distance from counted pool lengths
  - `length_count` — number of pool lengths completed
- **Physical-button control** — works with wet fingers and underwater.

## How to use

| Screen | Button | Action |
|--------|--------|--------|
| Idle | **START** | Begin prep breathe |
| Idle | **BACK** (short press) | Exit app |

[209 more lines in file. Use offset=36 to continue.]


edit

A personal, sideloaded Connect IQ app for the **Garmin fēnix 3** and **fēnix 3 HR** that records static breath-hold sessions and heart rate to a FIT file.

> **New design:** A full v2 design with a launch menu (Depth, Distance, Static Apnoe, Breathing Trainer) is documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). The current code is the original single-mode v1 breath-hold/pool-length app.

> **Important:** This app does **not** measure depth. The fēnix 3 *hardware* measures ambient pressure and the native *Ambient Press.* data field displays it, but the Connect IQ API on fēnix 3 (API Level 1.4.0) only exposes `Sensor.Info.pressure`. That value is **sea-level calibrated** and auto-corrected for weather/altitude, so a third-party app cannot read the raw ambient pressure needed for depth.

A personal, sideloaded Connect IQ app for the **Garmin fēnix 3** and **fēnix 3 HR** that records static breath-hold sessions and heart rate to a FIT file.

> **Important:** This app does **not** measure depth. The fēnix 3 *hardware* measures ambient pressure and the native *Ambient Press.* data field displays it, but the Connect IQ API on fēnix 3 (API Level 1.4.0) only exposes `Sensor.Info.pressure`. That value is **sea-level calibrated** and auto-corrected for weather/altitude, so a third-party app cannot read the raw ambient pressure needed for depth.


Successfully replaced 1 block(s) in /home/liph/code/garmin-freedive-app/README.md.

   1 # Garmin fēnix 3 Freedive Breath App
   2
   3 A personal, sideloaded Connect IQ app for the **Garmin fēnix 3** and **fēnix 3 HR** that records static breath-hold sessions and heart rate to a FIT file.
   4
+  5 > **New design:** A full v2 design with a launch menu (Depth, Distance, Static Apnoe, Breathing Trainer) is documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). The current code is the original single-mode v1 breath-hold/pool-length app.
+  6
   5 > **Important:** This app does **not** measure depth. The fēnix 3 *hardware* measures ambient pressure and the native *Ambient Press.* data field displays it, but the Connect IQ API on fēnix 3 (API Level 1.4.0) only exposes `Sensor.Info.pressure`. That value is **sea-level calibrated** and auto-corrected for weather/altitude, so a third-party app cannot read the raw ambient pressure needed for depth.
   6 >
   7 > **For depth logging on a fēnix watch**, use a **fēnix 5 / 5S / 5X / 5 Plus / 5S Plus / 5X Plus**. These support `Activity.Info.rawAmbientPressure` (API Level 2.4.0+) and forum reports indicate they do not artificially cap underwater pressure. Avoid the **fēnix 6 / 7 / 8 / Tactix** for depth-based freediving: reports say Garmin caps pressure readings underwater around 3 m, even though the raw-pressure API is present.
   8 >
     ...

--- /home/liph/code/garmin-freedive-app/README.md
+++ /home/liph/code/garmin-freedive-app/README.md
@@ -1,8 +1,10 @@
 # Garmin fēnix 3 Freedive Breath App

 A personal, sideloaded Connect IQ app for the **Garmin fēnix 3** and **fēnix 3 HR** that records static breath-hold sessions and heart rate to a FIT file.

+> **New design:** A full v2 design with a launch menu (Depth, Distance, Static Apnoe, Breathing Trainer) is documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). The current code is the original single-mode v1 breath-hold/pool-length app.
+
 > **Important:** This app does **not** measure depth. The fēnix 3 *hardware* measures ambient pressure and the native *Ambient Press.* data field displays it, but the Connect IQ API on fēnix 3 (API Level 1.4.0) only exposes `Sensor.Info.pressure`. That value is **sea-level calibrated** and auto-corrected for weather/altitude, so a third-party app cannot read the raw ambient pressure needed for depth.
 >
 > **For depth logging on a fēnix watch**, use a **fēnix 5 / 5S / 5X / 5 Plus / 5S Plus / 5X Plus**. These support `Activity.Info.rawAmbientPressure` (API Level 2.4.0+) and forum reports indicate they do not artificially cap underwater pressure. Avoid the **fēnix 6 / 7 / 8 / Tactix** for depth-based freediving: reports say Garmin caps pressure readings underwater around 3 m, even though the raw-pressure API is present.
 >


**Document status:** Pool-length horizontal distance feature implemented in §11.

---

# 12. Next Design — Multi-Discipline Menu

A complete v2 redesign is now documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). It adds a launch menu with four modes:

1. **Depth** — Constant Weight (bi-fins / monofin / no-fins) + Free Immersion (FIM), depth profile, dive time, HR, breath-up timer.
2. **Distance** — separate horizontal-distance mode (bi-fins / monofin / no-fins), manual lengths/strokes, breath-hold time, HR.
3. **Static Apnoe** — breath-up timer, breath-hold timer, recovery timer, HR.
4. **Breathing Trainer** — land-based CO₂/O₂ tables with decreasing rest times.

The design also includes FIT field IDs for all modes, screen layouts, and a phased implementation plan.

---


Successfully replaced 1 block(s) in /home/liph/code/garmin-freedive-app/IMPLEMENTATION_PLAN.md.

     ...
 443
 444 ---
 445
 446 **Document status:** Pool-length horizontal distance feature implemented in §11.
+447
+448 ---
+449
+450 # 12. Next Design — Multi-Discipline Menu
+451
+452 A complete v2 redesign is now documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). It adds a launch menu with four modes:
+453
+454 1. **Depth** — Constant Weight (bi-fins / monofin / no-fins) + Free Immersion (FIM), depth profile, dive time, HR, breath-up timer.
+455 2. **Distance** — separate horizontal-distance mode (bi-fins / monofin / no-fins), manual lengths/strokes, breath-hold time, HR.
+456 3. **Static Apnoe** — breath-up timer, breath-hold timer, recovery timer, HR.
+457 4. **Breathing Trainer** — land-based CO₂/O₂ tables with decreasing rest times.
+458
+459 The design also includes FIT field IDs for all modes, screen layouts, and a phased implementation plan.
+460
+461 ---

--- /home/liph/code/garmin-freedive-app/IMPLEMENTATION_PLAN.md
+++ /home/liph/code/garmin-freedive-app/IMPLEMENTATION_PLAN.md
@@ -443,4 +443,19 @@

 ---

 **Document status:** Pool-length horizontal distance feature implemented in §11.
+
+---
+
+# 12. Next Design — Multi-Discipline Menu
+
+A complete v2 redesign is now documented in [`APP_DESIGN_V2.md`](APP_DESIGN_V2.md). It adds a launch menu with four modes:
+
+1. **Depth** — Constant Weight (bi-fins / monofin / no-fins) + Free Immersion (FIM), depth profile, dive time, HR, breath-up timer.
+2. **Distance** — separate horizontal-distance mode (bi-fins / monofin / no-fins), manual lengths/strokes, breath-hold time, HR.
+3. **Static Apnoe** — breath-up timer, breath-hold timer, recovery timer, HR.
+4. **Breathing Trainer** — land-based CO₂/O₂ tables with decreasing rest times.
+
+The design also includes FIT field IDs for all modes, screen layouts, and a phased implementation plan.
+
+---


# Freedive App v2 Design — Main Menu + Multiple Disciplines

This document re-designs the app around a **main menu at launch** that lets you pick the discipline you are training. It is written primarily for the fēnix 5 depth build, but the non-depth modes also work on fēnix 3 (where depth simply stays 0 and `depth_m` is not written).

> **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.

---

## 1. Main Menu at Launch

When the app starts, the first screen is a 4-item menu:

```
+------------------+
|  FREEDIVE MODE   |
|                  |
| > Depth          |
|   Distance       |
|   Static Apnoe   |
|   Breathing Tr.  |
+------------------+
```

Navigation: **UP/DOWN** move the highlight, **START** selects the mode, **BACK** exits the app.

After selecting a mode you get a second menu for **fin type** (where applicable) or go straight into the session setup.

---

## 2. Mode: Depth

Sub-menu for fin type (only affects the FIT label; the watch still only measures vertical depth):

```
+------------------+
|  DEPTH FIN TYPE  |
|                  |
| > Constant Weight|
|   Free Immersion |
+------------------+
```

After choosing the discipline, choose the fin style (only relevant for Constant Weight):

```
+------------------+
|  CWT FIN STYLE   |
|                  |
| > Bi-fins        |
|   Monofin        |

[317 more lines in file. Use offset=51 to continue.]


Good, now I need to present this to the user and ask the clarifying questions. I'll keep it concise but cover the main points. I should ask the questions via ask_user_question since there are several concrete decisions needed.

Actually, the questions are a bit too many for one ask_user_question call (max 4 questions per invocation). I should prioritize the most important ones. Let me pick 4 questions:

1. Where to place Free Immersion (FIM) - under Depth or top-level?
2. In Distance mode, what should DOWN count - strokes or contractions? (or configurable)
3. Skip speed entirely, or derive approximate average speed from distance/hold time?
4. Implementation order - build menu + non-depth modes for fēnix 3 first, then fēnix 5 depth?

These are the most impactful decisions. The rest (breathing trainer defaults, etc.) I can make reasonable defaults for and they can adjust later.

Let me present the summary and ask the questions.

The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?

Choices:
Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.
Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.

Question: Where should Free Immersion (FIM) live?

Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.

Choices:
DOWN = one arm stroke. Useful for DYN/DNF technique analysis.
DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.
User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.

Question: What should DOWN count in Distance mode?

True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:

Choices:
Record distance, time, and strokes. Do not try to compute speed.
Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.

Question: How should we handle 'speed'?

The new design is a big refactor. Which order works best for you?

Choices:
Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.
Menu + non-depth modes for fēnix 3 first (Recommended)
Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.

Question: Implementation order?


Validation failed for tool "ask_user_question":
  - questions.0.header: must have required properties header
  - questions.1.header: must have required properties header
  - questions.2.header: must have required properties header
  - questions.3.header: must have required properties header

Received arguments:
{
  "questions": [
    {
      "description": "The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?",
      "options": [
        {
          "description": "Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.",
          "label": "Under Depth (Recommended)"
        },
        {
          "description": "Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.",
          "label": "Top-level item"
        }
      ],
      "question": "Where should Free Immersion (FIM) live?"
    },
    {
      "description": "Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.",
      "options": [
        {
          "description": "DOWN = one arm stroke. Useful for DYN/DNF technique analysis.",
          "label": "Count strokes"
        },
        {
          "description": "DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.",
          "label": "Count contractions"
        },
        {
          "description": "User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.",
          "label": "Configurable in settings (Recommended)"
        }
      ],
      "question": "What should DOWN count in Distance mode?"
    },
    {
      "description": "True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:",
      "options": [
        {
          "description": "Record distance, time, and strokes. Do not try to compute speed.",
          "label": "Skip speed entirely (Recommended)"
        },
        {
          "description": "Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.",
          "label": "Derive average speed after the fact"
        }
      ],
      "question": "How should we handle 'speed'?"
    },
    {
      "description": "The new design is a big refactor. Which order works best for you?",
      "options": [
        {
          "description": "Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.",
          "label": "Menu + non-depth modes for fēnix 3 first (Recommended)"
        },
        {
          "description": "Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.",
          "label": "Depth mode for fēnix 5 first"
        }
      ],
      "question": "Implementation order?"
    }
  ]
}


I see - the ask_user_question schema requires a "header" property, not "question". Let me fix that.

Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.

Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.

What should DOWN count in Distance mode?

DOWN = one arm stroke. Useful for DYN/DNF technique analysis.

DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.

User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.

Record distance, time, and strokes. Do not try to compute speed.

Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.

Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.

Menu + non-depth modes for fēnix 3 first (Recommended)

Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.


Validation failed for tool "ask_user_question":
  - questions.0.question: must have required properties question
  - questions.0.header: must not have more than 16 characters
  - questions.1.question: must have required properties question
  - questions.1.header: must not have more than 16 characters
  - questions.2.question: must have required properties question
  - questions.2.header: must not have more than 16 characters
  - questions.3.question: must have required properties question
  - questions.3.header: must not have more than 16 characters

Received arguments:
{
  "questions": [
    {
      "description": "The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?",
      "header": "Where should Free Immersion (FIM) live?",
      "options": [
        {
          "description": "Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.",
          "label": "Under Depth (Recommended)"
        },
        {
          "description": "Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.",
          "label": "Top-level item"
        }
      ]
    },
    {
      "description": "Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.",
      "header": "What should DOWN count in Distance mode?",
      "options": [
        {
          "description": "DOWN = one arm stroke. Useful for DYN/DNF technique analysis.",
          "label": "Count strokes"
        },
        {
          "description": "DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.",
          "label": "Count contractions"
        },
        {
          "description": "User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.",
          "label": "Configurable in settings (Recommended)"
        }
      ]
    },
    {
      "description": "True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:",
      "header": "How should we handle 'speed'?",
      "options": [
        {
          "description": "Record distance, time, and strokes. Do not try to compute speed.",
          "label": "Skip speed entirely (Recommended)"
        },
        {
          "description": "Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.",
          "label": "Derive average speed after the fact"
        }
      ]
    },
    {
      "description": "The new design is a big refactor. Which order works best for you?",
      "header": "Implementation order?",
      "options": [
        {
          "description": "Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.",
          "label": "Menu + non-depth modes for fēnix 3 first (Recommended)"
        },
        {
          "description": "Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.",
          "label": "Depth mode for fēnix 5 first"
        }
      ]
    }
  ]
}


The schema requires a "question" property (not "header") and the header must be <=16 characters. I think "question" is the actual question text and there might be a "label" or "header" short title. Let me look at the tool definition again.

The ask_user_question schema says:
- questions array items have properties: question (required), description, multiSelect, preview, options
- options have label, description, preview

And the error says "questions.0.header: must not have more than 16 characters" - so it seems there's a header property with max 16 chars. But also "questions.0.question: must have required properties question" means question should be an object? No, that doesn't make sense.

Wait, the error "must have required properties question" might mean the question object needs a "question" key. But I provided "header" instead of "question". And the header error is because it doesn't expect a "header" field at all? Or it does expect header but max 16 chars?

Let me try using "question" as the main text and maybe there's no header. The description can be longer. The label should be short.

Actually, looking at typical usage, the question object has:
- question: the short question text (maybe what I called header)
- description: longer explanation
- options: []

And the question text has a 16 char limit? That seems very short. Let me re-read: "questions.0.header: must not have more than 16 characters" - maybe the question field itself is called "header"? No.

Let me try a simpler approach. Maybe the schema is:
- question: object with required "question" (short) and optional "description" (longer)

But the error says "questions.0.question: must have required properties question" which implies question is itself an object that needs a "question" property. That's nested weird.

Actually I think the schema might be malformed in the description. Let me try this structure:
- question: { question: "short title", description: "longer text" }

No wait, looking at the error more carefully:
- "questions.0.question: must have required properties question" - this is saying the field "question" at index 0 must have required property "question". If "question" is the top-level field, then it must itself contain a "question" property. So maybe it's:

question: {
  question: "short text",
  description: "longer text"
}

And there's also a separate "header" field with max 16 chars. Let me try:

{
  header: "FIM location",  // <=16 chars
  question: {
    question: "Where should Free Immersion live?",
    description: "..."
  },
  options: [...]
}

Hmm, but the first error was "questions.0.header: must have required properties header" which means when I had "header" as a string, it expected it to be an object with "header" property. That doesn't make sense.

Actually I think the schema in the tool definition might be mis-described. Let me just try a minimal valid structure. Given the errors, I'll try:

{
  question: "Where should FIM live?",
  description: "longer text...",
  options: [...]
}

With "question" being a short string (<= maybe some limit). The error "questions.0.question: must have required properties question" might be a misinterpretation - maybe it means the object must have "question" property, which I didn't have because I used "header".

Let me try with "question" key and no "header".

Choices:
Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.
Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.

Question: FIM location

Choices:
DOWN = one arm stroke. Useful for DYN/DNF technique analysis.
DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.
User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.

Question: Distance DOWN action

Choices:
Record distance, time, and strokes. Do not try to compute speed.
Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.

Question: Speed handling

Choices:
Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.
Menu + non-depth modes for fēnix 3 first (Recommended)
Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.

Question: Build order


Validation failed for tool "ask_user_question":
  - questions.0.header: must have required properties header
  - questions.1.header: must have required properties header
  - questions.2.header: must have required properties header
  - questions.3.header: must have required properties header

Received arguments:
{
  "questions": [
    {
      "description": "The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?",
      "options": [
        {
          "description": "Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.",
          "label": "Under Depth (Recommended)"
        },
        {
          "description": "Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.",
          "label": "Top-level item"
        }
      ],
      "question": "FIM location"
    },
    {
      "description": "Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.",
      "options": [
        {
          "description": "DOWN = one arm stroke. Useful for DYN/DNF technique analysis.",
          "label": "Count strokes"
        },
        {
          "description": "DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.",
          "label": "Count contractions"
        },
        {
          "description": "User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.",
          "label": "Configurable in settings (Recommended)"
        }
      ],
      "question": "Distance DOWN action"
    },
    {
      "description": "True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:",
      "options": [
        {
          "description": "Record distance, time, and strokes. Do not try to compute speed.",
          "label": "Skip speed entirely (Recommended)"
        },
        {
          "description": "Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.",
          "label": "Derive average speed after the fact"
        }
      ],
      "question": "Speed handling"
    },
    {
      "description": "The new design is a big refactor. Which order works best for you?",
      "options": [
        {
          "description": "Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.",
          "label": "Menu + non-depth modes for fēnix 3 first (Recommended)"
        },
        {
          "description": "Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.",
          "label": "Depth mode for fēnix 5 first"
        }
      ],
      "question": "Build order"
    }
  ]
}


The schema seems to require "header" as an object with a "header" property. This is bizarre. Let me try:

{
  header: {
    header: "FIM location",
    description: "..."
  },
  options: [...]
}

No, that doesn't make sense either.

Actually, looking at the error again: "questions.0.header: must have required properties header" - it seems the validator thinks there should be a property "header" whose value is an object that must have a property also called "header". So:

questions[0] = {
  header: {
    header: "FIM location",
    ...
  }
}

But then where does the description go? Maybe:

questions[0] = {
  header: {
    header: "FIM location",
    description: "..."
  },
  options: [...]
}

This is weird but let me try it. The max 16 chars error was for the inner header string.


Validation failed for tool "ask_user_question":
  - questions.0.question: must have required properties question
  - questions.0.header: must be string
  - questions.1.question: must have required properties question
  - questions.1.header: must be string
  - questions.2.question: must have required properties question
  - questions.2.header: must be string
  - questions.3.question: must have required properties question
  - questions.3.header: must be string

Received arguments:
{
  "questions": [
    {
      "header": {
        "description": "The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?",
        "header": "FIM location"
      },
      "options": [
        {
          "description": "Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.",
          "label": "Under Depth (Recommended)"
        },
        {
          "description": "Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.",
          "label": "Top-level item"
        }
      ]
    },
    {
      "header": {
        "description": "Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.",
        "header": "Distance DOWN"
      },
      "options": [
        {
          "description": "DOWN = one arm stroke. Useful for DYN/DNF technique analysis.",
          "label": "Count strokes"
        },
        {
          "description": "DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.",
          "label": "Count contractions"
        },
        {
          "description": "User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.",
          "label": "Configurable in settings (Recommended)"
        }
      ]
    },
    {
      "header": {
        "description": "True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:",
        "header": "Speed handling"
      },
      "options": [
        {
          "description": "Record distance, time, and strokes. Do not try to compute speed.",
          "label": "Skip speed entirely (Recommended)"
        },
        {
          "description": "Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.",
          "label": "Derive average speed after the fact"
        }
      ]
    },
    {
      "header": {
        "description": "The new design is a big refactor. Which order works best for you?",
        "header": "Build order"
      },
      "options": [
        {
          "description": "Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.",
          "label": "Menu + non-depth modes for fēnix 3 first (Recommended)"
        },
        {
          "description": "Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.",
          "label": "Depth mode for fēnix 5 first"
        }
      ]
    }
  ]
}


Now the errors are clearer:
- header must be string
- question must have required properties question

So the structure is:
- header: string (short, <=16 chars)
- question: object with required property "question"
- options: array

So:
{
  header: "FIM location",
  question: {
    question: "Where should Free Immersion live?"
  },
  options: [...]
}

And description maybe goes inside question or is a separate field? Let me try with description as a top-level field or inside question. The error only complained about missing "question" inside "question". So question is an object { question: string, description?: string }.

Let me try this exact structure.

Choices:
Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.
Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.

The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?

Question: Where should Free Immersion live?

Choices:
DOWN = one arm stroke. Useful for DYN/DNF technique analysis.
DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.
User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.

Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.

Question: What should DOWN count in Distance mode?

Choices:
Record distance, time, and strokes. Do not try to compute speed.
Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.

True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:

Question: How should we handle speed?

Choices:
Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.
Menu + non-depth modes for fēnix 3 first (Recommended)
Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.

The new design is a big refactor. Which order works best for you?

Question: Implementation order?


Validation failed for tool "ask_user_question":
  - questions.0.question: must be string
  - questions.1.question: must be string
  - questions.2.question: must be string
  - questions.3.question: must be string

Received arguments:
{
  "questions": [
    {
      "header": "FIM location",
      "options": [
        {
          "description": "Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.",
          "label": "Under Depth (Recommended)"
        },
        {
          "description": "Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.",
          "label": "Top-level item"
        }
      ],
      "question": {
        "description": "The discipline you called 'immersions' is officially Free Immersion (FIM). It is usually grouped with depth disciplines because it is vertical. Should it be a sub-item under Depth (alongside Constant Weight), or its own top-level menu item?",
        "question": "Where should Free Immersion live?"
      }
    },
    {
      "header": "Distance DOWN",
      "options": [
        {
          "description": "DOWN = one arm stroke. Useful for DYN/DNF technique analysis.",
          "label": "Count strokes"
        },
        {
          "description": "DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.",
          "label": "Count contractions"
        },
        {
          "description": "User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.",
          "label": "Configurable in settings (Recommended)"
        }
      ],
      "question": {
        "description": "Distance mode is now a separate function. UP will count pool lengths. The DOWN button can count either arm strokes or contractions. We can also make it a setting.",
        "question": "What should DOWN count in Distance mode?"
      }
    },
    {
      "header": "Speed handling",
      "options": [
        {
          "description": "Record distance, time, and strokes. Do not try to compute speed.",
          "label": "Skip speed entirely (Recommended)"
        },
        {
          "description": "Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.",
          "label": "Derive average speed after the fact"
        }
      ],
      "question": {
        "description": "True speed cannot be measured underwater (no GPS, accelerometer dead-reckoning drifts too fast). Options:",
        "question": "How should we handle speed?"
      }
    },
    {
      "header": "Build order",
      "options": [
        {
          "description": "Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.",
          "label": "Menu + non-depth modes for fēnix 3 first (Recommended)"
        },
        {
          "description": "Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.",
          "label": "Depth mode for fēnix 5 first"
        }
      ],
      "question": {
        "description": "The new design is a big refactor. Which order works best for you?",
        "question": "Implementation order?"
      }
    }
  ]
}


Now it says "question must be string". So the "question" field should be a string, not an object. And presumably "description" is the longer text (top-level or inside question? but question is string only). Let me try:

{
  header: "FIM location",  // short <=16
  question: "Where should Free Immersion live?",  // string
  description: "longer text...",
  options: [...]
}

That should work based on the last error. The earlier error "questions.0.question: must have required properties question" was probably because I used "header" instead of "question" at top level, and the validator interpreted it weirdly. Now I know: top-level needs "question" as string, "header" as short string, "description" as longer text.

Choices:
Depth menu has two items: Constant Weight and Free Immersion. Simpler top-level menu.
Main menu becomes Depth, Distance, Free Immersion, Static Apnoe, Breathing Trainer. More explicit but busier.

Question: Where should Free Immersion live?

Choices:
DOWN = one arm stroke. Useful for DYN/DNF technique analysis.
DOWN = one diaphragm contraction. Keeps consistency with the old breath-hold app.
User picks whether DOWN counts strokes or contractions. A bit more code but most flexible.

Question: What should DOWN count in Distance mode?

Choices:
Record distance, time, and strokes. Do not try to compute speed.
Compute distance / breathhold_time and store it as a FIT session summary field. Not real-time but gives a rough average.

Question: How should we handle speed?

Choices:
Build the main menu, Static Apnoe, Distance, and Breathing Trainer so they work on your existing fēnix 3. Add fēnix 5 depth mode afterwards.
Menu + non-depth modes for fēnix 3 first (Recommended)
Focus on the fēnix 5 depth build first, then back-port the menu and non-depth modes.

Question: Implementation order?


User has answered your questions: "Where should Free Immersion live?"="Under Depth (Recommended)". "What should DOWN count in Distance mode?"="Configurable in settings (Recommended)". "How should we handle speed?"="Skip speed entirely (Recommended)". "Implementation order?"="make everything for fenix 5 forget the fenix 3". You can now continue with the user's answers in mind.

Question: Where should Free Immersion live?

Answer: Under Depth (Recommended)

Question: What should DOWN count in Distance mode?

Answer: Configurable in settings (Recommended)

Question: How should we handle speed?

Answer: Skip speed entirely (Recommended)

Question: Implementation order?

Answer: make everything for fenix 5 forget the fenix 3


Good, the user answered:
1. Free Immersion under Depth
2. DOWN in Distance mode: configurable (strokes or contractions)
3. Skip speed entirely
4. Implementation order: "make everything for fenix 5 forget the fenix 3" - so focus entirely on fēnix 5, not fēnix 3.

Now I should:
1. Update APP_DESIGN_V2.md with these decisions
2. Start implementing the v2 app for fēnix 5

Given the size, I should implement in phases. The user wants everything for fēnix 5. I should start with Phase 1: the menu shell + settings, then add modes one by one. But since they said "make everything for fenix 5" they want the full thing. I should probably implement a solid foundation first: main menu, settings, then depth, distance, static, breathing trainer.

Actually, I should be careful not to bite off too much in one turn. Let me plan the implementation:
- Create fēnix 5 manifest
- Create monkey_fenix5.jungle
- Create Common.mc with shared helpers
- Create Settings.mc (expanded)
- Create MainMenuView/MainMenuDelegate
- Create SubMenuView/SubMenuDelegate (reusable)
- Create DepthModel
- Create DepthView/DepthDelegate
- Create DistanceView/DistanceDelegate
- Create StaticView/StaticDelegate
- Create BreathingView/BreathingDelegate
- Maybe create FitRecorder helper
- Update build.sh or create build_fenix5.sh
- Update README

That's a lot of files. Given the conversation context, I should probably start implementing and aim to get a good chunk done. But it's a big refactor. Let me start with the foundational files: manifest, jungle, Common, Settings, MainMenu, SubMenu, and maybe the Depth mode since that's the primary fēnix 5 feature.

Actually, let me think about the architecture. Since we want a clean fēnix 5 build, I can create a new source tree or overlay. Maybe:
- source/Common.mc
- source/Settings.mc
- source/MainMenuView.mc
- source/MainMenuDelegate.mc
- source/SubMenuView.mc
- source/SubMenuDelegate.mc
- source/DepthModel.mc
- source/DepthView.mc
- source/DepthDelegate.mc
- source/DistanceView.mc
- source/DistanceDelegate.mc
- source/StaticView.mc
- source/StaticDelegate.mc
- source/BreathingView.mc
- source/BreathingDelegate.mc
- source/FitRecorder.mc

And a fēnix 5 specific entry:
- source/Fenix5App.mc (or DiveApp.mc)

But we also need to keep the fēnix 3 app working? The user said "forget the fenix 3" but that probably means focus on fēnix 5 for new features, not necessarily delete the fēnix 3 code. I should keep the existing fēnix 3 code and add a new build path for fēnix 5. The existing files can stay as they are, and we add new files for the v2 design.

Actually, the cleanest way is to have two apps in one project:
- v1: BreathHoldApp for fēnix 3
- v2: DiveApp for fēnix 5

Or we can make the v2 app the main app and have it support fēnix 5 only. But the user said "forget the fenix 3" which might mean they don't care if the fēnix 3 code is replaced. However, I should be safe and not delete the working fēnix 3 code. I'll create a new entry point and new views for fēnix 5.

Given the size, I think I should:
1. Update the design doc with the user's decisions
2. Create the fēnix 5 manifest and jungle
3. Create the shared foundation files (Common, Settings, MainMenu, SubMenu)
4. Create DepthModel and Depth mode
5. Update build script

Then in subsequent turns, add Distance, Static, Breathing Trainer modes.

Actually, I can create a lot of files in one turn since I have write/edit tools. But I need to be careful about not making mistakes. Let me start with the foundation and depth mode, which is the core fēnix 5 feature.

Let me update the design doc first, then start coding.

I’ve captured your decisions in the design doc:

- **Free Immersion (FIM)** lives under **Depth**.
- **Distance mode DOWN button** is **configurable** (strokes or contractions) in settings.
- **Speed** is **skipped entirely** — not measurable underwater.
- **Implementation focus:** fēnix 5 only.

I’ll now start building the v2 fēnix 5 app. First I’ll lay the foundation (manifest, menu system, shared helpers, settings), then implement the **Depth** mode, since that’s the main reason to target fēnix 5.

> **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.

## User decisions applied

- FIM is placed **under Depth**.
- Distance mode **DOWN** button is **configurable** as strokes or contractions.
- **Speed is skipped** — not measurable underwater.
- Development focus is **fēnix 5 only**; fēnix 3 v1 code is preserved but not extended.

---

## 1. Main Menu at Launch

> **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.

---

## 1. Main Menu at Launch


Successfully replaced 1 block(s) in /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md.

     ...
   3 This document re-designs the app around a **main menu at launch** that lets you pick the discipline you are training. It is written primarily for the fēnix 5 depth build, but the non-depth modes also work on fēnix 3 (where depth simply stays 0 and `depth_m` is not written).
   4
   5 > **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.
   6
+  7 ## User decisions applied
+  8
+  9 - FIM is placed **under Depth**.
+ 10 - Distance mode **DOWN** button is **configurable** as strokes or contractions.
+ 11 - **Speed is skipped** — not measurable underwater.
+ 12 - Development focus is **fēnix 5 only**; fēnix 3 v1 code is preserved but not extended.
+ 13
   7 ---
   8
   9 ## 1. Main Menu at Launch
  10
     ...

--- /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md
+++ /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md
@@ -3,8 +3,15 @@
 This document re-designs the app around a **main menu at launch** that lets you pick the discipline you are training. It is written primarily for the fēnix 5 depth build, but the non-depth modes also work on fēnix 3 (where depth simply stays 0 and `depth_m` is not written).

 > **Terminology check:** the discipline you called "*something* immersions" is officially **Free Immersion (FIM)** — you pull yourself up and down the line without fins.

+## User decisions applied
+
+- FIM is placed **under Depth**.
+- Distance mode **DOWN** button is **configurable** as strokes or contractions.
+- **Speed is skipped** — not measurable underwater.
+- Development focus is **fēnix 5 only**; fēnix 3 v1 code is preserved but not extended.
+
 ---

 ## 1. Main Menu at Launch


### Active session (Depth / Distance / Static / Breathing)

| Button | Action |
|--------|--------|
| START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
| UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
| DOWN | Depth/Distance mode: count a stroke **or** contraction based on the `distanceDownAction` setting |
| BACK short | Discard session and return to main menu |
| BACK long | Open in-session settings (rarely used) |

> In Distance mode the **DOWN** action is chosen in Settings: **strokes** or **contractions**.

### Active session (Depth / Distance / Static / Breathing)

| Button | Action |
|--------|--------|
| START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
| UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
| DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
| BACK short | Discard session and return to main menu |
| BACK long | Open in-session settings (rarely used) |

> **Open decision:** in Distance mode, should DOWN count **strokes** (arm pulls) or **contractions**? We could add a setting to choose which one DOWN counts.


Could not find the exact text in /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md. The old text must match exactly including all whitespace and newlines.


The edit failed because the text didn't match. Let me read the relevant section and try again.


| Button | Action |
|--------|--------|
| UP | Previous item |
| DOWN | Next item |
| START | Select / confirm |
| BACK short | Back one level / exit app if at top |
| BACK long | Open Settings |

### Active session (Depth / Distance / Static / Breathing)

| Button | Action |
|--------|--------|
| START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
| UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
| DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
| BACK short | Discard session and return to main menu |
| BACK long | Open in-session settings (rarely used) |

> **Open decision:** in Distance mode, should DOWN count **strokes** or **contractions**? They are different metrics. We could add a setting to choose which one DOWN counts.

---

## 8. Code Structure Changes

A single-file `BreathHoldView` is no longer enough. Proposed new files:

| File | Responsibility |
|------|--------------|
| `source/MainMenuApp.mc` | App entry point; loads settings; returns the main menu view |
| `source/MainMenuView.mc` + `MainMenuDelegate.mc` | Top-level 4-item menu |
| `source/SubMenuView.mc` + `SubMenuDelegate.mc` | Reusable 2–4 item sub-menu (fin type, breath-up length, etc.) |
| `source/Settings.mc` | Expanded persistence: pool length, water type, defaults, rest series |
| `source/DepthModel.mc` | Surface calibration, depth calculation, water density |
| `source/SessionState.mc` *(optional)* | Shared state machine constants and timer helpers |
| `source/DepthView.mc` + `DepthDelegate.mc` | Depth session UI and controls |
| `source/DistanceView.mc` + `DistanceDelegate.mc` | Distance session UI and controls |
| `source/StaticView.mc` + `StaticDelegate.mc` | Static apnoe session UI and controls |
| `source/BreathingView.mc` + `BreathingDelegate.mc` | Breathing trainer UI and controls |
| `source/FitRecorder.mc` *(optional)* | Central helper for creating/writing FIT fields per mode |
| `source/Common.mc` | Shared helpers (`formatTime`, HR sample, etc.) |

This is a significant refactor, but each mode becomes self-contained and easier to test.

---

## 9. FIT Field ID Allocation

Use a single ID space so one `.iq`/`.prg` does not collide. Recommended allocation:

| ID | Field | Message type |
|----|-------|--------------|
| 0 | `discipline` | SESSION |
| 1 | `depth_m` | RECORD |
| 2 | `hr_bpm` | RECORD |
| 3 | `max_depth_m` | SESSION |
| 4 | `dive_time_s` | SESSION |
| 5 | `surface_interval_s` | SESSION |
| 6 | `horizontal_distance_m` | SESSION |
| 7 | `length_count` | SESSION |
| 8 | `stroke_count` | SESSION |
| 9 | `breathhold_time_s` | SESSION |
| 10 | `breath_up_time_s` | SESSION |
| 11 | `recovery_time_s` | SESSION |
| 12 | `last_hr_bpm` | SESSION |
| 13 | `cycles_completed` | SESSION |
| 14 | `total_hold_time_s` | SESSION |
| 15 | `hold_target_s` | SESSION |
| 20 | `lap_hold_s` | LAP (Breathing trainer) |
| 21 | `lap_rest_s` | LAP (Breathing trainer) |

---

## 10. Implementation Phases

Because this is a large change, I suggest building it in phases:

1. **Phase 1 — Menu shell** (works on fēnix 3 too)
   - Replace the single `BreathHoldView` with `MainMenuView`.
   - Add sub-menu navigation.

[35 more lines in file. Use offset=340 to continue.]


### Active session (Depth / Distance / Static / Breathing)

| Button | Action |
|--------|--------|
| START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
| UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
| DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
| BACK short | Discard session and return to main menu |
| BACK long | Open in-session settings (rarely used) |

> **Open decision:** in Distance mode, should DOWN count **strokes** or **contractions**? They are different metrics. We could add a setting to choose which one DOWN counts.


     ...
 271 | Button | Action |
 272 |--------|--------|
 273 | START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
 274 | UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
-275 | DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
+275 | DOWN | Depth/Distance mode: count a stroke **or** contraction based on the `distanceDownAction` setting |
 276 | BACK short | Discard session and return to main menu |
 277 | BACK long | Open in-session settings (rarely used) |
 278
-279 > **Open decision:** in Distance mode, should DOWN count **strokes** or **contractions**? They are different metrics. We could add a setting to choose which one DOWN counts.
+279 > In Distance mode the **DOWN** action is chosen in Settings: **strokes** or **contractions**.
 280
 281 ---
 282
 283 ## 8. Code Structure Changes
     ...

--- /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md
+++ /home/liph/code/garmin-freedive-app/APP_DESIGN_V2.md
@@ -271,13 +271,13 @@
 | Button | Action |
 |--------|--------|
 | START | Skip breath-up / start dive / end dive / end hold / finish recovery / next cycle |
 | UP | Depth/Distance mode: count a length; Breathing trainer: adjust target up |
-| DOWN | Depth/Distance mode: count a stroke or contraction (user-pickable) |
+| DOWN | Depth/Distance mode: count a stroke **or** contraction based on the `distanceDownAction` setting |
 | BACK short | Discard session and return to main menu |
 | BACK long | Open in-session settings (rarely used) |

-> **Open decision:** in Distance mode, should DOWN count **strokes** or **contractions**? They are different metrics. We could add a setting to choose which one DOWN counts.
+> In Distance mode the **DOWN** action is chosen in Settings: **strokes** or **contractions**.

 ---

 ## 8. Code Structure Changes


   - Keep the existing Static/Recovery flow as one of the menu items.

2. **Phase 2 — Static Apnoe + Breathing Trainer** (works on fēnix 3 too)
   - Extract Static mode into its own view/delegate.
   - Add Breathing Trainer with configurable rest series and target hold.

3. **Phase 3 — Distance mode** (works on fēnix 3 too)
   - Move the manual pool-length logic out of the old breath-hold view into `DistanceView`.
   - Add fin-type selection and manual stroke counter.

4. **Phase 4 — Depth mode** (fēnix 5 only)
   - Create fēnix 5 build.
   - Add `DepthModel`, depth UI, depth FIT fields.

5. **Phase 5 — Polish**
   - Settings menu.
   - Common FIT helper.
   - README update.

---

## 11. Open Decisions Needed from You

Before I start coding, please confirm or correct these assumptions:

1. **Fin type selection** — keep the 3 options (bi-fins, monofin, no-fins) for both Depth and Distance?
2. **Free Immersion (FIM)** — should it appear under Depth alongside Constant Weight, or as its own top-level item?
3. **Strokes vs contractions** — in Distance mode, should DOWN count **strokes** (arm pulls) or **contractions**? We can make it configurable.
4. **Speed** — skip it entirely because it is not measurable underwater, or keep a manual stroke counter and derive an approximate average speed from `distance / breathhold_time` in the FIT summary?
5. **Breathing trainer defaults** — is the rest series `3:00 → 2:30 → 2:00 → 1:30 → 1:00` OK? How many cycles? Should target hold time be editable per session or only in settings?
6. **Build strategy** — should I implement the menu + non-depth modes first so they work on your existing fēnix 3, then create the fēnix 5 depth build?
7. **Depth on Static mode** — do you want the watch to also log depth/pressure while you do static breath-holds at the surface? (Normally it stays at 0 m.)

Once you confirm, I will start with **Phase 1** and update the code.


Because the user decided to focus on **fēnix 5**, the phases are adjusted:

1. **Phase 1 — fēnix 5 manifest + menu shell + settings**
   - Create `manifest_fenix5.xml` / `monkey_fenix5.jungle`.
   - Build `MainMenuView`, `SubMenuView`, expanded `Settings`, and shared `Common`/`DepthModel`.

2. **Phase 2 — Depth mode** (fēnix 5)
   - Add `DepthView`/`DepthDelegate` with surface calibration, depth graph, and session summary fields.

3. **Phase 3 — Distance mode**
   - Add `DistanceView`/`DistanceDelegate` with fin-type selection, configurable DOWN action, pool length, and manual length/stroke counting.

4. **Phase 4 — Static Apnoe + Breathing Trainer**
   - Add `StaticView`/`StaticDelegate` and `BreathingView`/`BreathingDelegate`.

5. **Phase 5 — Polish**
   - Add settings menu, `FitRecorder` helper, build script, and README update.

---

## 11. Open Decisions Applied

- FIM lives **under Depth**.
- Distance **DOWN** is **configurable** (strokes or contractions).
- **Speed is skipped** entirely.
- Development focus is **fēnix 5 only**; fēnix 3 v1 code is preserved but not extended.
- Remaining defaults (breathing trainer rest series, cycles, etc.) use the values in §5 unless the user changes them later.

Because this is a large change, I suggest building it in phases:

1. **Phase 1 — Menu shell** (works on fēnix 3 too)
   - Replace the single `BreathHoldView` with `MainMenuView`.
   - Add sub-menu navigation.
   - Keep the existing Static/Recovery flow as one of the menu items.

2. **Phase 2 — Static Apnoe + Breathing Trainer** (works on fēnix 3 too)
   - Extract Static mode into its own view/delegate.
   - Add Breathing Trainer with configurable rest series and target hold.

3. **Phase 3 — Distance mode** (works on fēnix 3 too)
   - Move the manual pool-length logic out of the old breath-hold view into `DistanceView`.
   - Add fin-type selection and manual stroke counter.

4. **Phase 4 — Depth mode** (fēnix 5 only)
   - Create fēnix 5 build.
   - Add `DepthModel`, depth UI, depth FIT fields.

5. **Phase 5 — Polish**
   - Settings menu.
   - Common FIT helper.
   - README update.

---

## 11. Open Decisions Needed from You

Before I start coding, please confirm or correct these assumptions:

1. **Fin type selection** — keep the 3 options (bi-fins, monofin, no-fins) for both Depth and Distance?
2. **Free Immersion (FIM)** — should it appear under Depth alongside Constant Weight, or as its own top-level item?
3. **Strokes vs contractions** — in Distance mode, should DOWN count **strokes** (arm pulls) or **contractions**? We could make it configurable.
4. **Speed** — skip it entirely because it is not measurable underwater, or keep a manual stroke counter and derive an approximate average speed from `distance / breathhold_time` in the FIT summary?
5. **Breathing trainer defaults** — is the rest series `3:00 → 2:30 → 2:00 → 1:30 → 1:00` OK? How many cycles? Should target hold time be editable per session or only in settings?
6. **Build strategy** — should I implement the menu + non-depth modes first so they work on your existing fēnix 3, then create the fēnix 5 depth build?
7. **Depth on Static mode** — do you want the watch to also log depth/pressure while you do static breath-holds at the surface? (Normally it stays at 0 m.)

Once you confirm, I will start with **Phase 1** and update the code.


The edit failed again because of whitespace. I need to match exactly. Let me read the exact section and then edit.


   - Replace the single `BreathHoldView` with `MainMenuView`.
   - Add sub-menu navigation.
   - Keep the existing Static/Recovery flow as one of the menu items.

2. **Phase 2 — Static Apnoe + Breathing Trainer** (works on fēnix 3 too)
   - Extract Static mode into its own view/delegate.
   - Add Breathing Trainer with configurable rest series and target hold.

3. **Phase 3 — Distance mode** (works on fēnix 3 too)
   - Move the manual pool-length logic out of the old breath-hold view into `DistanceView`.
   - Add fin-type selection and manual stroke counter.

4. **Phase 4 — Depth mode** (fēnix 5 only)
   - Create fēnix 5 build.
   - Add `DepthModel`, depth UI, depth FIT fields.

5. **Phase 5 — Polish**
   - Settings menu.
   - Common FIT helper.
   - README update.

---

## 11. Open Decisions Needed from You

Before I start coding, please confirm or correct these assumptions:

1. **Fin type selection** — keep the 3 options (bi-fins, monofin, no-fins) for both Depth and Distance?
2. **Free Immersion (FIM)** — should it appear under Depth alongside Constant Weight, or as its own top-level item?
3. **Strokes vs contractions** — in Distance mode, should DOWN count **strokes** (arm pulls) or **contractions**? We can make it configurable.
4. **Speed** — skip it entirely because it is not measurable underwater, or keep a manual stroke counter and derive an approximate average speed from `distance / breathhold_time` in the FIT summary?
5. **Breathing trainer defaults** — is the rest series `3:00 → 2:30 → 2:00 → 1:30 → 1:00` OK? How many cycles? Should target hold time be editable per session or only in settings?
6. **Build strategy** — should I implement the menu + non-depth modes first so they work on your existing fēnix 3, then create the fēnix 5 depth build?
7. **Depth on Static mode** — do you want the watch to also log depth/pressure while you do static breath-holds at the surface? (Normally it stays at 0 m.)

Once you confirm, I will start with **Phase 1** and update the code.


I see the issue - my oldText had extra content at the beginning that didn't match. Let me just replace from "## 10. Implementation Phases" onwards with the new content. Actually, I can use smaller unique snippets. Let me replace the open decisions section only.

Actually, instead of continuing to struggle with exact text matching, I can just note that the design doc has been updated enough for now and move on to coding. The user's answers are clear. I don't need to perfectly update the design doc right now; I can update it later. The main thing is to start implementing.

Let me start creating the files. I'll create:
1. manifest_fenix5.xml
2. monkey_fenix5.jungle
3. source/Common.mc
4. source/Settings.mc (expanded, will overwrite the old one but old fēnix 3 code might break - the user said forget fēnix 3. Actually, I should NOT overwrite the old Settings.mc because the old fēnix 3 app uses it. I should create a new Settings file or adapt it to work for both. Hmm.)

Wait - the user said "make everything for fenix 5 forget the fenix 3". That could mean they want me to replace the project with a fēnix 5 only app. But I think it's safer to create new files for the v2 app and leave v1 intact. However, if I create a new Settings.mc it will overwrite the old one.

Better approach: create a new directory structure for v2, e.g. `source/v2/` or keep v1 files and create `source/Fenix5Settings.mc`. But the manifest entry point can only point to one AppBase class. For fēnix 5 build, I can use a new AppBase class and new views. The old Settings.mc would only be used by the old BreathHoldApp (which is not in fēnix 5 manifest).

Actually, I can create a unified Settings that works for both, but that complicates things. Given the user said forget fēnix 3, I'll create a new, expanded Settings.mc and update the old BreathHoldApp to use it minimally, OR I can keep the old Settings and create Fenix5Settings.

Given that the user wants fēnix 5 focus, and the fēnix 3 code is "preserved but not extended", I think the cleanest is to create new v2 files with their own names and leave v1 files alone. But `Settings.mc` is a generic name. Let me use `AppSettings.mc` for the v2 settings, and keep `Settings.mc` for v1. The v2 app will use AppSettings.

Actually, that's getting messy. Let me think differently: since the user said "forget the fenix 3", they might be okay with replacing the project. But I should still keep the design doc and maybe the old files as backup. However, I shouldn't just delete working code without need.

Best compromise: create new source files for the v2 fēnix 5 app with distinct names, and adjust the manifest to point to a new entry class. The old fēnix 3 files stay. For settings, I'll create `AppSettings.mc` for v2.

Let me create:
- `manifest_fenix5.xml`
- `monkey_fenix5.jungle`
- `source/Common.mc`
- `source/AppSettings.mc`
- `source/MainMenuApp.mc`
- `source/MainMenuView.mc`
- `source/MainMenuDelegate.mc`
- `source/SubMenuView.mc`
- `source/SubMenuDelegate.mc`
- `source/DepthModel.mc`
- `source/DepthView.mc`
- `source/DepthDelegate.mc`

And maybe a `build_fenix5.sh` script.

That's a lot. Let me start creating them one by one. I'll use write for new files.

Let me think about the content carefully.

### Common.mc
Shared helpers:
- formatTime(seconds)
- getHeartRate() -> returns last HR or null

### AppSettings.mc
Expanded settings:
- poolLengthM, poolLengthIndex
- waterType (fresh/salt)
- defaultBreathUpTime
- defaultRecoveryTime
- distanceDownAction (strokes/contractions)
- breathingRestSeries (array of seconds)
- breathingHoldTarget
- staticBreathUpTime, staticRecoveryTime

Methods: load(), save()

### MainMenuApp.mc
AppBase subclass, entry point. Loads settings. Returns MainMenuView + MainMenuDelegate.

### MainMenuView.mc / MainMenuDelegate.mc
Show 4 items:
- Depth
- Distance
- Static Apnoe
- Breathing Trainer

UP/DOWN move, START selects, BACK exits.

### SubMenuView.mc / SubMenuDelegate.mc
Reusable menu. Takes title, items array, and a callback method.

### DepthModel.mc
Depth calculation using Activity.Info.rawAmbientPressure.

### DepthView.mc / DepthDelegate.mc
Depth session UI. States:
- CONFIG: choose discipline (CWTB, CWT-M, CNF, FIM) - actually use SubMenu before
- BREATH_UP
- SURFACE
- DIVE
- RECOVERY
- DONE

Actually, the menu system will handle discipline selection before launching DepthView. So DepthView will be given the discipline string.

For this first implementation turn, I'll create the menu system and DepthModel + a basic DepthView. Maybe I won't fully implement DepthView's FIT recording yet, but I should get the structure right.

Let me create the files now. I'll be careful with Monkey C syntax.

Actually, given the complexity and the risk of making errors, I should create the foundation first and make sure it's coherent. Let me write the files.

write

<?xml version="1.0"?>
<iq:manifest xmlns:iq="http://www.garmin.com/connect-iq" version="1">
    <iq:application entry="Fenix5App" id="b896271ba7e04e12988fd03fb8714fc4" minApiLevel="2.4.0" type="watch-app" name="@Strings.AppName">
        <iq:products>
            <iq:product id="fenix5"/>
            <iq:product id="fenix5s"/>
            <iq:product id="fenix5x"/>
            <iq:product id="fenix5plus"/>
            <iq:product id="fenix5splus"/>
            <iq:product id="fenix5xplus"/>
        </iq:products>
        <iq:permissions>
            <iq:permission id="Sensor"/>
            <iq:permission id="ActivityRecording"/>
            <iq:permission id="FitContributor"/>
        </iq:permissions>
        <iq:languages>
            <iq:language>eng</iq:language>
        </iq:languages>
    </iq:application>
</iq:manifest>

project.manifest = manifest_fenix5.xml
base.sourcePath = source
base.resourcePath = resources


Successfully wrote 839 bytes to /home/liph/code/garmin-freedive-app/manifest_fenix5.xml


Successfully wrote 94 bytes to /home/liph/code/garmin-freedive-app/monkey_fenix5.jungle